Fixed- and especially mobile-networks, such as Global System for Mobile communications (GSM), General Packet Radio System (GPRS) or Universal Mobile Telecommunication System (UMTS) are constantly evolving. GSM/GPRS and UMTS networks today offer both Circuit Switched (CS) connectivity and Packet Switched (PS) connectivity. The PS end-to-end connectivity with its terminal capabilities for transmission of a wide range of data types may be used for offering multimedia services such as image, music and video transfer. The CS connectivity provides a reliable link between two User Equipment by means of one or more trusted network nodes with a reliable and defined Quality of Service (QoS).
Combinational networks, where two or more links of different type to one or more User Equipment or terminals are established, are capable to deploy both CS and PS connectivity to a User Equipment, thereby enabling services which perform their activity through PS-communication sessions, denoted as PS-sessions, and CS communication sessions, denoted as CS calls.
As to benefit from this form of service combination, User Equipment are required that are capable of handling a CS call and a PS-session simultaneously. Multi Radio Access Bearer (RAB) terminals for UMTS and Dual Transfer Mode (DTM) terminals for GSM/GPRS networks will be available; these types of terminals provide support for simultaneous CS- and PS-connectivity.
Today, conversational voice cannot be delivered over PS bearers to the end user, due to insufficient capacity in the Radio Access Networks in operation and therefore existing CS bearers are used for delivering conversational voice. In the future, it may be possible that a single PS bearer is used for conversational voice and multimedia. Nevertheless, DTM terminals today-, and UMTS terminals in the future, will deliver support for simultaneous CS- and PS-connectivity.
Using the simultaneous connectivity, a party denoted here as A-party browses Internet (establish a PS-session) while talking to another party, denoted here as B-party, via a voice-call via a CS network. Simultaneity, however, does not necessarily imply that the ongoing CS-call is related to the ongoing PS-session.
In contrast to this when the A-party, which has an ongoing CS-call with the B-party, sends a picture showing how beautiful the snow outside the house looks, while talking about the weather, the picture transferred in a PS-session and the ongoing CS-call are related from the A-party's perspective. The PS-session, though, can be established in such a way that it is functionally identical to an uncorrelated web-browsing session.
Suppose that said A-party calls, by means of a CS-call, the B-party by using B-party's name from an address book, related to the CS-network. When the A-party needs to post a picture to the B-party, while talking to the B-party, the A-party has to browse through his/her “PS address book” to transfer the picture. A PS-session is established with the B-party, completely independent of the ongoing CS-call. In this example, there is no interaction between the user interfaces, or the network components—the correlation takes place in the users' head.
In the foregoing example, it would be desirable if the A-party had the possibility to send the picture to the B-party—the B-Party from the CS address book. The A-party should have a possibility to choose: “Send the picture to my CS-call partner” such that the A-party is relieved from having to browse any address book.
When a service residing in the network, and/or client software in the terminal or User Equipment becomes aware (or is made aware) of the relation between the CS-call and the PS-session, the CS-call and PS-session become correlated from that service’ viewpoint, and a service thus provided is referred to as a combinational service. An important issue in the combinational service, in particular in the foregoing example, is addressing, i.e. “How to get the address of the PS-domain part of the B-party's phone, terminal or User Equipment?” Another issue is, when the A-party sends a picture to the B-party, he/she would also like the picture to actually arrive on B-party's terminal or User Equipment. Additionally the A-party should know that the B-party has a terminal or User Equipment that is actually capable of receiving A-party's PS-session based message. I.e. how does the A-party get to know about the B-party's terminal capabilities?
In order to give the A-party the best possible user experience, it should be possible for certain icons to light up (or even appear) on the Graphical User Interface (GUI) of the A-party's terminal that inform him/her about the availability of various possibilities to communicate with the B-party. For instance, if the B-party has a DTM terminal, a “picture messaging” icon should light up on A-party's terminal User Equipment.
The problem to be solved is: (1) how can the A-party get the PS-session addressing information of the B-party and the PS-session terminal capabilities of the B-party's terminal or User Equipment (the terminal of the “CS-call partner”), when a CS-call is established or after a CS-call has been established between the A-party and the B-party, and (2) how can the B-party get the PS-session addressing information of the A-party and the PS-session terminal capabilities of the A-party's terminal or User Equipment?
Prior art solutions to the problem posed are provided by patent application US 2003/0026394 A1 [Chapman et al.] and U.S. Pat. No. 5,949,763 [Lund].
Chapman et al. discloses a system and method for establishing a voice and related data connection over disparate networks, wherein a voice connection telephone number determines an associated data destination by means of a query to a network database i.e. a local database, or a hybrid number register for said data destination. This, performed by a network node or Mobile Switching Centre, and provides the destination, such as an IP-address, to a Packet control Unit.
Lund describes a system and method for establishing a voice and data connection from a terminal connected to a central office by means of a loop pairs or DSL connection, carrying both voice and data, towards a subscriber, via a PSTN and data network, where an SCP queries a network database, as to check the configuration of the calling and called party's terminals and retrieves the IP data addresses, and sends the data addresses towards the Customer Premise Equipment (CPE) terminals for establishing a data-connection.